Fix: If default domain is premium for free users do not offer it as an option (#1763)

* Fix: If default domain is premium for free users do not offer it as an option

* Refactored into simpler logic

---------

Co-authored-by: Adrià Casajús <adria.casajus@proton.ch>

app/alias_suffix.py

@@ -169,8 +169,11 @@ def get_alias_suffixes(
             alias_suffixes.insert(0, alias_suffix)
 
     if not default_domain_found:
-        sl_domain = SLDomain.get(user.default_alias_public_domain_id)
-        if sl_domain and not sl_domain.hidden:
+        domain_conditions = {"id": user.default_alias_public_domain_id, "hidden": False}
+        if not user.is_premium():
+            domain_conditions["premium_only"] = False
+        sl_domain = SLDomain.get_by(**domain_conditions)
+        if sl_domain:
             prefix = (
                 ""
                 if config.DISABLE_ALIAS_SUFFIX

tests/test_alias_suffixes.py

@@ -84,6 +84,28 @@ def test_get_default_domain_hidden():
     assert suffixes[0].domain != default_domain.domain
 
 
+def test_get_default_domain_is_premium_for_free_user():
+    user = create_new_user()
+    PartnerUser.create(
+        partner_id=get_proton_partner().id,
+        user_id=user.id,
+        external_user_id=random_token(10),
+        flush=True,
+    )
+    user.trial_end = None
+    default_domain = SLDomain.filter_by(partner_id=None, premium_only=True).first()
+    user.default_alias_public_domain_id = default_domain.id
+    Session.flush()
+    options = AliasOptions(
+        show_sl_domains=False, show_partner_domains=get_proton_partner()
+    )
+    suffixes = get_alias_suffixes(user, alias_options=options)
+    for suffix in suffixes:
+        domain = SLDomain.get_by(domain=suffix.domain)
+        assert not domain.premium_only
+    assert suffixes[0].domain != default_domain.domain
+
+
 def test_suffixes_are_valid():
     user = create_new_user()
     PartnerUser.create(